US4239627A - Filtering member and method for manufacturing the same - Google Patents
Filtering member and method for manufacturing the same Download PDFInfo
- Publication number
- US4239627A US4239627A US06/073,034 US7303479A US4239627A US 4239627 A US4239627 A US 4239627A US 7303479 A US7303479 A US 7303479A US 4239627 A US4239627 A US 4239627A
- Authority
- US
- United States
- Prior art keywords
- cylindrical body
- filtering
- filtering member
- resilient
- sheet
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
Links
- 238000001914 filtration Methods 0.000 title claims abstract description 71
- 238000000034 method Methods 0.000 title claims description 15
- 238000004519 manufacturing process Methods 0.000 title claims description 5
- 239000012535 impurity Substances 0.000 claims abstract description 26
- 239000011148 porous material Substances 0.000 claims abstract description 12
- 239000012530 fluid Substances 0.000 claims abstract description 7
- 239000012858 resilient material Substances 0.000 claims abstract description 4
- 229920003002 synthetic resin Polymers 0.000 claims abstract description 4
- 239000000057 synthetic resin Substances 0.000 claims abstract description 4
- 238000004804 winding Methods 0.000 claims abstract description 4
- 239000004744 fabric Substances 0.000 claims abstract description 3
- 230000007423 decrease Effects 0.000 claims description 4
- 239000011796 hollow space material Substances 0.000 claims 5
- 230000003247 decreasing effect Effects 0.000 abstract 1
- 239000007788 liquid Substances 0.000 description 7
- 239000002184 metal Substances 0.000 description 7
- 239000000463 material Substances 0.000 description 6
- 238000011144 upstream manufacturing Methods 0.000 description 2
- 229920002678 cellulose Polymers 0.000 description 1
- 239000001913 cellulose Substances 0.000 description 1
- 239000002131 composite material Substances 0.000 description 1
- 238000010276 construction Methods 0.000 description 1
- 230000006866 deterioration Effects 0.000 description 1
- 239000013013 elastic material Substances 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 230000002035 prolonged effect Effects 0.000 description 1
Images
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D27/00—Cartridge filters of the throw-away type
- B01D27/04—Cartridge filters of the throw-away type with cartridges made of a piece of unitary material, e.g. filter paper
Definitions
- This invention relates to a filtering member and more particularly to a cylindrical filtering member for use in an oil cleaner and the like.
- impurities in a liquid are collected in a number of capillary spaces each having a sufficient length viewed in a direction of a liquid flow as well as in a number of small spaces in the bulk of the filtering member.
- impurities are collected in the bulk of filtering material in a three dimensional manner and thus a great number of impurities can be filtered out by means of a filtering member having a relatively small volume.
- An ideal filtering member for the bulk filtering should have pores of large size at an upstream side and should have pores of small size at a downstream side viewed in a direction of a liquid flow. Then large impurities are collected at the upstream portion and small impurities at the downstream portion of the filtering member. In this manner the impurities of various sizes can be effectively collected in the bulk of the filtering member. Therefore the deterioration of the filtering material occurs equally or evenly at various portions thereof and thus the filtering efficiency is materially prolonged. From this view point a plurality of filtering layers having different porosities are stuck one upon the other to form a laminated filtering member. However such a filtering member is quite complicated in construction and can be manufactured only with difficulty. Therefore the cost of such a filtering member becomes rather high.
- the present invention has for its object to provide a novel filtering member which can effectively collect impurities of various sizes.
- a filtering member for collecting impurities of different sizes contained in a fluid in a bulk filtering mode comprising a substantially cylindrical body made of resilient and porous material, the cylindrical body having a porosity which decreases gradually toward a center of the cylindrical body.
- the present invention also relates to a method for manufacturing a filtering member for use in a bulk filtering process.
- a method for manufacturing a filtering member for use in filtering impurities of different sizes contained in a fluid in a bulk filtering mode comprising a step of clamping a sheet like member made of resilient and porous material between a pair of resilient plates, the sheet like member having a uniform porosity over its thickness;
- said plates of sheet like members are formed by metal meshes and an assembly of the filtering member and the metal meshes are installed in a casing of a filter.
- FIG. 1 is a partial perspective view illustrating a starting state of a filtering member according to the invention
- FIG. 2 is a perspective view showing an embodiment of a filtering member according to the invention.
- FIGS. 3a and 3b are schematic views for explaining a change in porosity of the filtering material.
- FIG. 4 is a partial cross section depicting a filter having the filtering member according to the invention installed therein.
- FIG. 1 shows a sheet like member 1 made of resilient and porous filtering material such as fabric, porous synthetic resin, etc.
- the sheet like member 1 has a uniform porosity over its whole thickness.
- the sheet like member 1 is sandwiched between a pair of resilient plates 2 and 3 made of elastic material such as rubber and a whole assembly is deformed or wound into a cylindrical body as shown in FIG. 2.
- a mandrel may be preferrably used to wind thereon the assembly of the sheet like member 1 and resilient plates 2 and 3.
- An inner portion of the sheet like member 1 adjacent to the inner plate 2 is compressed, but an outer portion of the member 1 adjacent to the outer plate 3 is expanded.
- the porosity of the inner portion of the sheet like member 1 becomes smaller, but that of the outer portion becomes larger.
- FIG. 3a when the sheet like member 1 is in a flat form, its porosity is substantially uniform over its whole thickness but when the sheet like member 1 is wound into the cylindrical body, a side ab is expanded, but a side cd is shrunk. Therefore the size of pores formed in the sheet like member 1 becomes larger toward the outer portion but becomes smaller toward the inner portion. In this manner it is possible to obtain easily a filtering member having a porosity which decreases gradually toward a center of the cylindrical body.
- the cylindrical filtering member 4 thus obtained is installed in a filter 5 as illustrated in FIG. 4.
- the filter 5 comprises a tubular casing 6 made of suitable metal.
- the casing 6 has an opening formed at its one side and the opening is closed by a flange 6A and a lid 6B.
- the lid 6B has formed therein an oil inlet 7 and an oil outlet 8.
- a frame 9 comprising upper and lower discs 12 and 11 and inner and outer apertured cylindrical bodies 14 and 13 made of wire grating or mesh, punched metal plate.
- the frame 9 is held in the casing 6 by means of coiled spring 10.
- the filtering member 4 is provided in a space formed between the inner and outer cylindrical meshes 14 and 13. It should be noted the resilient plates 2 and 3 shown in FIG. 2 are removed.
- An oil having impurities to be filtered out is introduced into the casing 6 through the inlet 7. Then the oil passes through the openings of outer cylindrical mesh 13 and passes through the filtering member 4 according to the invention from the outside to the inside. During the passage of the oil the impurities therein are filtered out in the bulk of the filtering member 4. In this case the impurities of larger size are collected in the outer portion of the filtering member, whereas the smaller impurities are collected in the inner portion of the filtering member 4. In this manner the impurities having different sizes are uniformly deposited over the whole thickness of the filtering member 4. Therefore no cake is formed near the outer cylindrical mesh 13 and thus the filter 5 can maintain the high filtering efficiency during its long life time.
- the present invention is not limited to the embodiment explained above, but many modifications can be conceived within the scope of the invention.
- the sheet like member 1 is deformed into a cylindrical body with the aid of the rubber plates 2 and 3, but use may be made of metal meshes.
- the assembly of the sheet like member and metal meshes may be directly fit in the filter casing. That is to say the metal meshes may be used as the cylindrical bodies 13 and 14 shown in FIG. 4.
- the size of pores varies continuously or gradually viewed in the direction of the fluid flow and thus the impurities of various sizes can be effectively collected uniformly in the bulk of the filtering member. In this manner the ideal bulk filtering can be achieved. Further the filtering member according to the invention can be easily manufactured and its cost can be made materially low.
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- Chemical & Material Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Filtering Materials (AREA)
Abstract
A filtering member for use in a filter such as an oil filter for removing impurities of different sizes contained in a fluid such as a working oil in an oil pressure apparatus comprises a cylindrical body made of resilient or flexible and porous material such as fabrics, porous synthetic resin, etc, the porosity of the cylindrical body decreasing gradually toward a center thereof. The filtering member can be easily and inexpensively manufactured by winding or deforming a sheet like member made of resilient material having a uniform porosity over its thickness into a cylindrical body in such a manner that an outer portion is expanded or stretched, but an inner portion is compressed.
Description
This invention relates to a filtering member and more particularly to a cylindrical filtering member for use in an oil cleaner and the like.
There have been developed various kinds of filtering methods. These methods can be roughly classified into a surface filtering method and a bulk filtering method. In the surface filtering method impurities or admixtures contained in a liquid to be treated are collected or filtered out at a surface of a filtering member, i.e. a filtering material. When the impurities are deposited on the surface of a filtering member, resistance against a flow of the liquid passing therethrough is gradually increased and at last pores in the surface are completely clogged by the collected impurities, so that the filtering operation can no longer be effected. Therefore it is necessary to use a filtering member which has a very large surface area. This results in increase in size of a filter in which such a large filtering member is installed. On the contrary in the bulk filtering method impurities in a liquid are collected in a number of capillary spaces each having a sufficient length viewed in a direction of a liquid flow as well as in a number of small spaces in the bulk of the filtering member. In this manner the impurities are collected in the bulk of filtering material in a three dimensional manner and thus a great number of impurities can be filtered out by means of a filtering member having a relatively small volume.
By means of the bulk filtering method in order to remove impurities of different sizes in a liquid such as a working oil which circulates in an oil pressure apparatus use may be made of a composite body of cellulose having continuous pores, a sintered body, foamed synthetic resin, etc. However since the size of the impurities varies over a very wide range it is quite difficult to select suitable filtering material. If fine impurities are to be collected, a filtering member might be clogged within a relatively short time, and thus in order to prolong a useful time the filtering member has to be formed in such a manner that only impurities having large size can be collected. Then small impurities might remain in the oil without being filtered out and might damage the oil pressure apparatus. An ideal filtering member for the bulk filtering should have pores of large size at an upstream side and should have pores of small size at a downstream side viewed in a direction of a liquid flow. Then large impurities are collected at the upstream portion and small impurities at the downstream portion of the filtering member. In this manner the impurities of various sizes can be effectively collected in the bulk of the filtering member. Therefore the deterioration of the filtering material occurs equally or evenly at various portions thereof and thus the filtering efficiency is materially prolonged. From this view point a plurality of filtering layers having different porosities are stuck one upon the other to form a laminated filtering member. However such a filtering member is quite complicated in construction and can be manufactured only with difficulty. Therefore the cost of such a filtering member becomes rather high.
The present invention has for its object to provide a novel filtering member which can effectively collect impurities of various sizes.
It is another object of the invention to provide a filtering member which can maintain its very high filtering efficiency over its long life time.
It is still another object of the invention to provide a filtering member which has a porosity profile changing uniformly in the direction of the liquid flow.
According to the invention a filtering member for collecting impurities of different sizes contained in a fluid in a bulk filtering mode is provided comprising a substantially cylindrical body made of resilient and porous material, the cylindrical body having a porosity which decreases gradually toward a center of the cylindrical body.
The present invention also relates to a method for manufacturing a filtering member for use in a bulk filtering process.
It is still another object of the invention to provide a novel method for manufacturing a filtering member in a simple and inexpensive manner.
According to the invention a method for manufacturing a filtering member for use in filtering impurities of different sizes contained in a fluid in a bulk filtering mode is provided comprising a step of clamping a sheet like member made of resilient and porous material between a pair of resilient plates, the sheet like member having a uniform porosity over its thickness; and
a step for winding an assembly of the sheet like member and the resilient plates into a substantially cylindrical body in such a manner that an outer portion of the cylindrical body is stretched, whereas an inner portion of the cylindrical body is compressed.
In a preferred embodiment of the invention said plates of sheet like members are formed by metal meshes and an assembly of the filtering member and the metal meshes are installed in a casing of a filter.
FIG. 1 is a partial perspective view illustrating a starting state of a filtering member according to the invention;
FIG. 2 is a perspective view showing an embodiment of a filtering member according to the invention;
FIGS. 3a and 3b are schematic views for explaining a change in porosity of the filtering material; and
FIG. 4 is a partial cross section depicting a filter having the filtering member according to the invention installed therein.
FIG. 1 shows a sheet like member 1 made of resilient and porous filtering material such as fabric, porous synthetic resin, etc. In a free state shown in FIG. 1 the sheet like member 1 has a uniform porosity over its whole thickness. According to the invention the sheet like member 1 is sandwiched between a pair of resilient plates 2 and 3 made of elastic material such as rubber and a whole assembly is deformed or wound into a cylindrical body as shown in FIG. 2. During this step a mandrel may be preferrably used to wind thereon the assembly of the sheet like member 1 and resilient plates 2 and 3. An inner portion of the sheet like member 1 adjacent to the inner plate 2 is compressed, but an outer portion of the member 1 adjacent to the outer plate 3 is expanded. Thus the porosity of the inner portion of the sheet like member 1 becomes smaller, but that of the outer portion becomes larger. As shown in FIG. 3a when the sheet like member 1 is in a flat form, its porosity is substantially uniform over its whole thickness but when the sheet like member 1 is wound into the cylindrical body, a side ab is expanded, but a side cd is shrunk. Therefore the size of pores formed in the sheet like member 1 becomes larger toward the outer portion but becomes smaller toward the inner portion. In this manner it is possible to obtain easily a filtering member having a porosity which decreases gradually toward a center of the cylindrical body.
The cylindrical filtering member 4 thus obtained is installed in a filter 5 as illustrated in FIG. 4. The filter 5 comprises a tubular casing 6 made of suitable metal. The casing 6 has an opening formed at its one side and the opening is closed by a flange 6A and a lid 6B. The lid 6B has formed therein an oil inlet 7 and an oil outlet 8. In the casing 6 is arranged a frame 9 comprising upper and lower discs 12 and 11 and inner and outer apertured cylindrical bodies 14 and 13 made of wire grating or mesh, punched metal plate. The frame 9 is held in the casing 6 by means of coiled spring 10. The filtering member 4 is provided in a space formed between the inner and outer cylindrical meshes 14 and 13. It should be noted the resilient plates 2 and 3 shown in FIG. 2 are removed.
An oil having impurities to be filtered out is introduced into the casing 6 through the inlet 7. Then the oil passes through the openings of outer cylindrical mesh 13 and passes through the filtering member 4 according to the invention from the outside to the inside. During the passage of the oil the impurities therein are filtered out in the bulk of the filtering member 4. In this case the impurities of larger size are collected in the outer portion of the filtering member, whereas the smaller impurities are collected in the inner portion of the filtering member 4. In this manner the impurities having different sizes are uniformly deposited over the whole thickness of the filtering member 4. Therefore no cake is formed near the outer cylindrical mesh 13 and thus the filter 5 can maintain the high filtering efficiency during its long life time.
The present invention is not limited to the embodiment explained above, but many modifications can be conceived within the scope of the invention. For instance, in the above embodiment the sheet like member 1 is deformed into a cylindrical body with the aid of the rubber plates 2 and 3, but use may be made of metal meshes. In such a case the assembly of the sheet like member and metal meshes may be directly fit in the filter casing. That is to say the metal meshes may be used as the cylindrical bodies 13 and 14 shown in FIG. 4.
As explained above in the filtering member according to the invention the size of pores varies continuously or gradually viewed in the direction of the fluid flow and thus the impurities of various sizes can be effectively collected uniformly in the bulk of the filtering member. In this manner the ideal bulk filtering can be achieved. Further the filtering member according to the invention can be easily manufactured and its cost can be made materially low.
Claims (6)
1. A filtering member for collecting impurities of different sizes contained in a fluid in a bulk filtering mode comprising:
a substantially cylindrical body made of resilient and porous materials and formed by winding a rectangular sheet of resilient and uniformly porous material by one turn to form a central hollow space, the cylindrical body having a porosity which decreases gradually toward the central hollow space viewed in a radial direction, wherein the fluid to be filtered flows from an outer surface of the cylindrical body to the central hollow space.
2. A filtering member according to claim 1, wherin said cylindrical body is made of fabrics.
3. A filtering member according to claim 1, wherein said cylindrical body is made of porous synthetic resin.
4. A method for manufacturing a filtering member for use in filtering impurities of different sizes contained in a fluid in a bulk filtering mode comprising:
preparing a rectangular sheet of resilient and uniformly porous material;
clamping the sheet between a pair of resilient plates; and
winding an assembly of the sheet and the resilient plates by one turn into a substantially cylindrical body having a central hollow space in such a manner that an outer portion of the cylindrical body is stretched and an inner portion of the cylindrical body is compressed, and the cylindrical body has a porosity gradient which decreases gradually towards the center hollow space viewed in a radial direction.
5. A method according to claim 4, wherein the assembly of the sheet like member and the resilient plates is wound into the substantially cylindrical body with the aid of a tubular mandrel.
6. A method according to claim 4, wherein a pair of wire meshes are used as said resilient plates.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP1979034621U JPS55137908U (en) | 1979-03-16 | 1979-03-16 | |
| JP54-34621[U] | 1979-03-16 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| US4239627A true US4239627A (en) | 1980-12-16 |
Family
ID=12419449
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| US06/073,034 Expired - Lifetime US4239627A (en) | 1979-03-16 | 1979-09-06 | Filtering member and method for manufacturing the same |
Country Status (2)
| Country | Link |
|---|---|
| US (1) | US4239627A (en) |
| JP (1) | JPS55137908U (en) |
Cited By (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB2177316A (en) * | 1985-06-28 | 1987-01-21 | Dequinre Limited | Oil filter element |
| US4836931A (en) * | 1986-04-16 | 1989-06-06 | Porous Media Corporation | Reinforced filter tube and method of making the same |
| US4923333A (en) * | 1988-05-12 | 1990-05-08 | Timmons Robert D | Lysimeter for leak detection and method of assembly thereof |
| GB2230205A (en) * | 1989-04-11 | 1990-10-17 | Seitz Filter Werke | Filter element |
| US5269921A (en) * | 1989-04-11 | 1993-12-14 | Seitz-Filter-Werke Gmbh & Co. | Filter cartridge or filter module consisting of flexible deep filter material |
| US20060049094A1 (en) * | 2002-10-25 | 2006-03-09 | Philippe Lescoche | Membrane for tangential filtration and production method thereof |
| US20080203011A1 (en) * | 2004-04-23 | 2008-08-28 | Philippe Lescoche | Support Having an Altered Porosity and Membrane for the Tangential Flow Filtration |
| RU2458727C1 (en) * | 2011-03-14 | 2012-08-20 | Государственное образовательное учреждение высшего профессионального образования "Томский государственный архитектурно-строительный университет" (ГОУ ВПО "ТГАСУ") | Filtration element |
| RU2535050C1 (en) * | 2013-06-27 | 2014-12-10 | Федеральное государственное бюджетное образовательное учреждение высшего профессионального образования "Томский государственный архитектурно-строительный университет" (ТГАСУ) | Filter |
| CN107076487A (en) * | 2014-10-23 | 2017-08-18 | 三菱电机株式会社 | oil separator |
| RU2774164C1 (en) * | 2021-05-27 | 2022-06-15 | Федеральное государственное бюджетное образовательное учреждение высшего образования "Российский государственный аграрный университет - МСХА имени К.А. Тимирязева" (ФГБОУ ВО РГАУ - МСХА имени К.А. Тимирязева) | Reusable cellular filter |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US2083546A (en) * | 1933-06-20 | 1937-06-15 | Aldham Thomas Edward | Oil filter |
| US3807570A (en) * | 1972-09-29 | 1974-04-30 | Carborundum Co | Slot depth filter element |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS457580Y1 (en) * | 1967-01-25 | 1970-04-11 |
-
1979
- 1979-03-16 JP JP1979034621U patent/JPS55137908U/ja active Pending
- 1979-09-06 US US06/073,034 patent/US4239627A/en not_active Expired - Lifetime
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US2083546A (en) * | 1933-06-20 | 1937-06-15 | Aldham Thomas Edward | Oil filter |
| US3807570A (en) * | 1972-09-29 | 1974-04-30 | Carborundum Co | Slot depth filter element |
Cited By (16)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB2177316A (en) * | 1985-06-28 | 1987-01-21 | Dequinre Limited | Oil filter element |
| GB2177316B (en) * | 1985-06-28 | 1989-07-19 | Dequinre Limited | Filter |
| US4836931A (en) * | 1986-04-16 | 1989-06-06 | Porous Media Corporation | Reinforced filter tube and method of making the same |
| US4923333A (en) * | 1988-05-12 | 1990-05-08 | Timmons Robert D | Lysimeter for leak detection and method of assembly thereof |
| GB2230205A (en) * | 1989-04-11 | 1990-10-17 | Seitz Filter Werke | Filter element |
| US5122270A (en) * | 1989-04-11 | 1992-06-16 | Seitz-Filter-Werke Theo & Geo Seitz Gmbh & Co. | Filter cartridge or filter module consisting of flexible deep filter material |
| GB2230205B (en) * | 1989-04-11 | 1993-02-24 | Seitz Filter Werke | Filter element |
| US5269921A (en) * | 1989-04-11 | 1993-12-14 | Seitz-Filter-Werke Gmbh & Co. | Filter cartridge or filter module consisting of flexible deep filter material |
| US20060049094A1 (en) * | 2002-10-25 | 2006-03-09 | Philippe Lescoche | Membrane for tangential filtration and production method thereof |
| US20080203011A1 (en) * | 2004-04-23 | 2008-08-28 | Philippe Lescoche | Support Having an Altered Porosity and Membrane for the Tangential Flow Filtration |
| RU2458727C1 (en) * | 2011-03-14 | 2012-08-20 | Государственное образовательное учреждение высшего профессионального образования "Томский государственный архитектурно-строительный университет" (ГОУ ВПО "ТГАСУ") | Filtration element |
| RU2535050C1 (en) * | 2013-06-27 | 2014-12-10 | Федеральное государственное бюджетное образовательное учреждение высшего профессионального образования "Томский государственный архитектурно-строительный университет" (ТГАСУ) | Filter |
| CN107076487A (en) * | 2014-10-23 | 2017-08-18 | 三菱电机株式会社 | oil separator |
| US20170276415A1 (en) * | 2014-10-23 | 2017-09-28 | Mitsubishi Electric Corporation | Oil separator |
| US11015850B2 (en) * | 2014-10-23 | 2021-05-25 | Mitsubishi Electric Corporation | Oil separator |
| RU2774164C1 (en) * | 2021-05-27 | 2022-06-15 | Федеральное государственное бюджетное образовательное учреждение высшего образования "Российский государственный аграрный университет - МСХА имени К.А. Тимирязева" (ФГБОУ ВО РГАУ - МСХА имени К.А. Тимирязева) | Reusable cellular filter |
Also Published As
| Publication number | Publication date |
|---|---|
| JPS55137908U (en) | 1980-10-01 |
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